| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a pressure reducing exhaust valve which is applicable to a pressure reducing device having only one exhaust passage (a main exhaust passage), fast in exhaust velocity and capable of suppressing the soaring of particles, and also to provide a pressure reducing device using a pressure reducing exhaust mechanism including the same. Ž<P>SOLUTION: The pressure reducing exhaust valve 10 is attached in a portion of the exhaust passage, one end of which is communicated with a vacuum chamber, and the other end with the vacuum pump. This exhaust valve 10 also includes: a valve body 11 and a ball valve body 12, which is accommodated rotatably inside the valve body 11, in which communication holes formed inside are branched into at least three holes, and in which a porous body 13 with vent pores is arranged in one of the communication holes. In accordance with the rotation position of the ball valve body in the valve body, the exhaust valve 10 is structured to be capable of selecting a closed valve state, an open valve state via the porous body, and an open valve state not via the porous body. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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